I know it’s boring but you can exercise all you want and have the healthiest diet, but if you are not in a calorie deficit, you will not lose weight, if you are not in a surplus, you will not gain weight- and that's the bottom line!
BEFORE READING THIS PLS NOTE, THERE IS AN ONLINE CALCULATOR THAT WILL WORK OUT THE BELOW FOR YOU: https://tdeecalculator.net/
To achieve your goals, try and stick to your unique calorie count as much as possible. Logging your food with aps like My Fitness Pal is helpful for tracking and once you have logged your food for 4-5 days, you should get the gist of things.
Before you begin, you need to figure out how many calories you need to be consuming per day to maintain your current weight. To find this out, you need to know your Basal Metabolic Rate (BMR).This is the calories your body uses to perform basic actions to keep you alive such as breathing, circulating blood and basic brain function.
STEP 1: CALCULATE YOUR BMR
BMR = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (years) – 161
e.g. my BMR is (10 x 73) + (6.25 x 165) – (5 x 27) – 161 = 1465.25
STEP 2: CALCULATE YOUR DAILY CALORIE NEEDS (DCN)
Multiply your Physical Activity Level (PAL)- see below, by your BMR to find out how many calories your body needs, taking into account your physical activity level throughout the day.
THE ACTIVITY LEVELS:
Inactive (little or no exercise) =BMR x 1.2
Lightly active (light exercise/sports 1-3 days/week) =BMR x 1.37
Moderately active (moderate exercise/sports 3-5 days/week) =BMR x 1.55
Very active (hard exercise/sports 6-7 days a week) =BMR x 1.725
e.g. my PAL would be very active = 1465 x 1.725 = 2527.55
This means my Daily Calorie Needs (DCN) is 2527 calories per day to maintain my current weight.
SO HOW MANY CALORIES DO I NEED TO LOSE/ GAIN WEIGHT?
A deficit of 500 calories per day, which is equivalent to 3500 calories per week, should result in 1 pound of weight loss per week and the reverse is true for a surplus of 500 calories per day.
Exercise provides an excellent method of creating a greater calorie deficit- if this is your goal
If your goal is weight loss: Number of calories to consume per day = DCN - 500 calories
If your goal is weight gain: Number of calories to consume per day = DCN + 500 calories
If your goal is to maintain: Consume your DCN
There are some online calcultors that calculate this for you. Check out https://tdeecalculator.net/
You will need to plus or minus 500 calories from the Total Energy Expenditure number for your weight gain or weight loss goal.